Add tests for TextProtoReader.readMIMEHeader()

Original: 36edda18ab

headers.ts

@@ -0,0 +1,34 @@
+// Fake headers to work around
+// https://github.com/denoland/deno/issues/1173
+
+function normalize(name: string, value?: string): [string, string] {
+  name = String(name).toLowerCase();
+  value = String(value).trim();
+  return [name, value];
+}
+
+export class Headers {
+  private map = new Map<string, string>();
+
+  get(name: string): string | null {
+    let [name_] = normalize(name);
+    return this.map.get(name_);
+  }
+
+  append(name: string, value: string): void {
+    [name, value] = normalize(name, value);
+    this.map.set(name, value);
+  }
+
+  toString(): string {
+    let out = "";
+    this.map.forEach((v, k) => {
+      out += `${k}: ${v}\n`;
+    });
+    return out;
+  }
+
+  [Symbol.iterator](): IterableIterator<[string, string]> {
+    return this.map[Symbol.iterator]();
+  }
+}